A seat pumping device for a vehicle in the related art refers to a device which is attached to a seat in order to allow an occupant seated in the seat to manually adjust a height of a seat cushion in accordance with his/her body type. When the occupant seated in the seat manipulates a lever handle, which is installed at a lateral side of the seat cushion, clockwise or counterclockwise, operating force of the lever handle is transmitted to a link mechanism through the seat pumping device, such that the seat cushion moves upward or downward in response to a direction in which the lever handle is manipulated.
The seat pumping device for a vehicle has been publicly known through Korean Patent Nos. 10-0722849 and 10-0784620.
FIG. 1 illustrates an example of the seat pumping device for a vehicle. However, the seat pumping device for a vehicle, which will be described with reference to FIGS. 1 to 5, is considered as the related art in the present specification, but the seat pumping device for a vehicle has not been publicly known, and it should be understood that a description of the seat pumping device for a vehicle is just made to explain the background for the purpose of deriving the present invention.
A seat pumping device for a vehicle includes a lever bracket 100 which is integrally rotatably connected to a lever handle (not illustrated) manipulated by a user, a return spring guide 110 which accommodates return springs 112 that provide restoring force to the lever bracket 100, a housing 120 which is installed in a seat cushion (not illustrated) and has a shape of a drum 122, a clutch device 130 which is accommodated in the housing 120, receives rotational manipulation force from the user through the lever bracket 100, and transmits the rotational manipulation force, a brake device 140 which blocks reversely inputted torque and maintains an adjusted height of the seat cushion, and a housing cover 150 which is coupled to one side of the housing 120 and covers the housing 120.
One side of the return spring guide 110 may be formed in the form of a doughnut having a concave groove so as to accommodate the return springs 112.
The clutch device 130 includes a clutch cam 134 which is accommodated in a clutch drum 132, a plurality of clutch rollers 136 which is installed between an outer circumferential surface of the clutch cam 134 and an inner circumferential surface of the clutch drum 132, and clutch springs 138 which resiliently support the clutch rollers 136.
A plurality of coupling protrusions 135 is formed on one surface of the clutch cam 134 at a predetermined interval in a circumferential direction.
A through hole 126, into which the coupling protrusions 135 of the clutch cam 134 are inserted, is formed at a central portion of a bottom surface 124 of the drum 122 of the housing 120.
The lever bracket 100 may include a coupling drum 104 that protrudes in an axial direction.
Referring to FIG. 2, a plurality of assembly holes 128 is formed at a predetermined interval in the circumferential direction at the periphery of the through hole 126 at the center of the bottom surface of the drum 122 of the housing 120, and a plurality of assembly protrusions 114, which is inserted into and coupled to the assembly holes 128 and protrudes in the axial direction, is formed on the return spring guide 110 so as to be disposed at a predetermined interval in the circumferential direction. The return springs 112 may be provided so as to surround an outer side of the assembly protrusions 114.
Therefore, when the assembly protrusions 114 of the return spring guide 110 are inserted into and coupled to the assembly holes 128 of the housing 120, the return spring guide 110 comes into close contact with the bottom surface 124 of the drum 122 of the housing 120, as illustrated in FIG. 3. In addition, the return spring guide 110 is fixedly coupled to the housing 120 so as not to be rotatable relative to the housing 120 by an interaction between the assembly holes 128 and the assembly protrusions 114.
Referring to FIG. 4, the coupling protrusions 135 of the clutch cam 134 protrude through the through hole 126 at the center of the housing 120, and is integrally coupled to the lever bracket 100 by being inserted into the assembly holes formed in a bottom surface of the drum 104 of the lever bracket 100.
For example, the lever bracket 100 is integrally coupled to the coupling protrusions 135 of the clutch cam 134 by welding, such that the lever bracket 100 and the clutch cam 134 rotate together.
A lever arm 102, which is formed on the lever bracket 100 by being bent in the axial direction, is resiliently supported in the circumferential direction by the return springs 112 of the return spring guide 110, such that when the lever bracket 100 is rotated as the user manipulates the lever handle, the return springs 112 are compressed by the lever arm 102 of the lever bracket 100, and then provide elastic restoring force to the lever bracket 100.
However, as illustrated in FIG. 5, when the coupling protrusions 135 of the clutch cam 134 and the lever bracket 100 are coupled by welding, the lever bracket 100 excessively comes into close contact with an outer circumferential surface of the return spring guide 110. Therefore, when the lever bracket 100 is rotated by the manipulation of the lever handle, the lever bracket 100 is rotated in the state in which the lever bracket 100 is excessively in close contact with the outer circumferential surface of the return spring guide 110, and as a result, there is a problem in that excessive frictional force is generated between the lever bracket 100 and the outer circumferential surface of the return spring guide 110, which causes deterioration in operating characteristics of the lever handle.